cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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industrialio-triggered-buffer.c (3823B)

      1// SPDX-License-Identifier: GPL-2.0-only
      2 /*
      3 * Copyright (c) 2012 Analog Devices, Inc.
      4 *  Author: Lars-Peter Clausen <lars@metafoo.de>
      5 */
      6
      7#include <linux/kernel.h>
      8#include <linux/export.h>
      9#include <linux/module.h>
     10#include <linux/iio/iio.h>
     11#include <linux/iio/buffer.h>
     12#include <linux/iio/buffer_impl.h>
     13#include <linux/iio/kfifo_buf.h>
     14#include <linux/iio/triggered_buffer.h>
     15#include <linux/iio/trigger_consumer.h>
     16
     17/**
     18 * iio_triggered_buffer_setup_ext() - Setup triggered buffer and pollfunc
     19 * @indio_dev:		IIO device structure
     20 * @h:			Function which will be used as pollfunc top half
     21 * @thread:		Function which will be used as pollfunc bottom half
     22 * @direction:		Direction of the data stream (in/out).
     23 * @setup_ops:		Buffer setup functions to use for this device.
     24 *			If NULL the default setup functions for triggered
     25 *			buffers will be used.
     26 * @buffer_attrs:	Extra sysfs buffer attributes for this IIO buffer
     27 *
     28 * This function combines some common tasks which will normally be performed
     29 * when setting up a triggered buffer. It will allocate the buffer and the
     30 * pollfunc.
     31 *
     32 * Before calling this function the indio_dev structure should already be
     33 * completely initialized, but not yet registered. In practice this means that
     34 * this function should be called right before iio_device_register().
     35 *
     36 * To free the resources allocated by this function call
     37 * iio_triggered_buffer_cleanup().
     38 */
     39int iio_triggered_buffer_setup_ext(struct iio_dev *indio_dev,
     40	irqreturn_t (*h)(int irq, void *p),
     41	irqreturn_t (*thread)(int irq, void *p),
     42	enum iio_buffer_direction direction,
     43	const struct iio_buffer_setup_ops *setup_ops,
     44	const struct attribute **buffer_attrs)
     45{
     46	struct iio_buffer *buffer;
     47	int ret;
     48
     49	buffer = iio_kfifo_allocate();
     50	if (!buffer) {
     51		ret = -ENOMEM;
     52		goto error_ret;
     53	}
     54
     55	indio_dev->pollfunc = iio_alloc_pollfunc(h,
     56						 thread,
     57						 IRQF_ONESHOT,
     58						 indio_dev,
     59						 "%s_consumer%d",
     60						 indio_dev->name,
     61						 iio_device_id(indio_dev));
     62	if (indio_dev->pollfunc == NULL) {
     63		ret = -ENOMEM;
     64		goto error_kfifo_free;
     65	}
     66
     67	/* Ring buffer functions - here trigger setup related */
     68	indio_dev->setup_ops = setup_ops;
     69
     70	/* Flag that polled ring buffering is possible */
     71	indio_dev->modes |= INDIO_BUFFER_TRIGGERED;
     72
     73	buffer->direction = direction;
     74	buffer->attrs = buffer_attrs;
     75
     76	ret = iio_device_attach_buffer(indio_dev, buffer);
     77	if (ret < 0)
     78		goto error_dealloc_pollfunc;
     79
     80	return 0;
     81
     82error_dealloc_pollfunc:
     83	iio_dealloc_pollfunc(indio_dev->pollfunc);
     84error_kfifo_free:
     85	iio_kfifo_free(buffer);
     86error_ret:
     87	return ret;
     88}
     89EXPORT_SYMBOL(iio_triggered_buffer_setup_ext);
     90
     91/**
     92 * iio_triggered_buffer_cleanup() - Free resources allocated by iio_triggered_buffer_setup_ext()
     93 * @indio_dev: IIO device structure
     94 */
     95void iio_triggered_buffer_cleanup(struct iio_dev *indio_dev)
     96{
     97	iio_dealloc_pollfunc(indio_dev->pollfunc);
     98	iio_kfifo_free(indio_dev->buffer);
     99}
    100EXPORT_SYMBOL(iio_triggered_buffer_cleanup);
    101
    102static void devm_iio_triggered_buffer_clean(void *indio_dev)
    103{
    104	iio_triggered_buffer_cleanup(indio_dev);
    105}
    106
    107int devm_iio_triggered_buffer_setup_ext(struct device *dev,
    108					struct iio_dev *indio_dev,
    109					irqreturn_t (*h)(int irq, void *p),
    110					irqreturn_t (*thread)(int irq, void *p),
    111					enum iio_buffer_direction direction,
    112					const struct iio_buffer_setup_ops *ops,
    113					const struct attribute **buffer_attrs)
    114{
    115	int ret;
    116
    117	ret = iio_triggered_buffer_setup_ext(indio_dev, h, thread, direction,
    118					     ops, buffer_attrs);
    119	if (ret)
    120		return ret;
    121
    122	return devm_add_action_or_reset(dev, devm_iio_triggered_buffer_clean,
    123					indio_dev);
    124}
    125EXPORT_SYMBOL_GPL(devm_iio_triggered_buffer_setup_ext);
    126
    127MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
    128MODULE_DESCRIPTION("IIO helper functions for setting up triggered buffers");
    129MODULE_LICENSE("GPL");